The Opposition's health spokeswoman Catherine King said Senator Nash was "engaging in a debate about semantics in order to protect herself", and called on Prime Minister Tony Abbott to "consider the case".

"Why did the minister decide to intervene?" Ms King said.

"Did she declare the issue she was supposed to declare, and what has happened between her office and the Prime Minister's office."

However, Federal Health Minister Peter Dutton has backed his junior minister, while not responding to concerns raised about the management of the star rating website.